示例#1
0
 // Read up to 'len' bytes of Value. Value should already be persisted to
 // disk.  A racing delete can trigger a failure where we get a null return,
 // but no crash (although one could argue that a racing load&delete is a bug
 // no matter what).
 @Override
 public byte[] load(Value v) {
   long skip = 0;
   Key k = v._key;
   // Convert an arraylet chunk into a long-offset from the base file.
   if (k._kb[0] == Key.ARRAYLET_CHUNK) {
     skip = ValueArray.getChunkOffset(k); // The offset
     k = ValueArray.getArrayKey(k); // From the base file key
   }
   if (k._kb[0] == Key.DVEC) {
     skip = water.fvec.NFSFileVec.chunkOffset(k); // The offset
   }
   try {
     FileInputStream s = null;
     try {
       s = new FileInputStream(getFileForKey(k));
       FileChannel fc = s.getChannel();
       fc.position(skip);
       AutoBuffer ab = new AutoBuffer(fc, true, Value.NFS);
       byte[] b = ab.getA1(v._max);
       ab.close();
       assert v.isPersisted();
       return b;
     } finally {
       if (s != null) s.close();
     }
   } catch (IOException e) { // Broken disk / short-file???
     H2O.ignore(e);
     return null;
   }
 }